As a member of Team 404, HK416 is typically a quiet T-doll, she would speak a little bit more in front of her companions, but it is often foul mouthing. Oppose to her cold demeanor and personality, she shows great performance in terms of physical maneuvers and reflexes.
She is a very arrogant figure, believing herself to be the pinnacle of combat performance and the finest T-Doll IOP has ever manufactured. Boasting aside, HK416 is actually a very reliable T-doll in combat and to her companions. She places her trust in her squad leader, SMG UMP45UMP45 's decisions, though she frequently complains about them.
Due to the poor conditions 404 frequently resides in (alongside other reasons), HK416 holds a deep grudge against the members of the AR team. She is very much jealous of the resources and facilities AR team have access to. Her grudges are especially aimed against AR M16A1M16A1 and AR M4A1M4A1 .
One of the furniture states "Don't give Alcohol to HK-416" which may indicate that HK has a low tolerance to alcohol.
A developed model of HK416 is chambered for 7.62x51mm NATO calibre is named HK417, Bundeswehr enlisted the DMR variant of HK417 (HK241) to service under the designation G28, hence HK416 and RF G28G28 are described as sisters by the player base. Some of G28's quotations even mentions her big sister 416.
Squad 404 is in S09 to extract information. After accomplishing their objective, HK416 takes the opportunity to try to get revenge on M16A1. She is unsuccessful, for—although M16A1 is in a weakened state—the latter T-Doll still proves to be a superior combatant. UMP45 interrupts their fun to retrieve one frustrated HK416.
Special Delivery to Sector S09
SMG MP5MP5 was tasked with resupply and Intel collection mission in Sector S09, HK416 made an minor appearance with G11 during this small covert operation.
Helian contracts Squad 404 to assist with the search for AR-15 in S06. Their first objective is to locate and retrieve the jammer, so they target Hunter, the ringleader stationed to protect the object of interest. However, they all initially underestimate Hunter’s abilities due to the ringleader’s “Elite” modification and thus are forced to retreat. Squad 404 emerges victorious against the ringleader after having engaged in guerilla warfare. HK416 moves to wake her, but they are unable to gain information from her because Ouroburos shuts down Hunter’s neural cloud. UMP45 orders HK416 to take the other two members of Squad 404 to the other side of the sector.
After the unsuccessful endeavor involving Hunter, the group heads towards a safe zone within S06. They receive the coordinates of the jammer from SPP-1, a scout from Griffin who has been separated from her escort. Then, they all make their way to the zone with the jammer, but are stopped by Executioner—who happens to be guarding the jammer, and has also received an “Elite” modification . They deal with Executioner in the same fashion as they did with Hunter. However, Executioner has set up explosives throughout the area as a last ditch measure to take out Squad 404. No harm comes their way because UMP45 successfully negotiates with the ringleader to let them escape the blast radius in exchange for returning Hunter.
Ouroboros is intent on hunting down Squad 404, so UMP45 concocts a plan to defeat her. HK416 is ordered to carry G11 to a vantage point in R13 so that G11 can cover their withdrawal and after placing her down, she is then to work alongside OTs-14, an elite Griffin T-Doll who had been escorting SPP-1, with wearing down Ouroboros’s forces.
Eventually, Griffin and Squad 404 emerge victorious. HK416 waits outside the command post for UMP45 to return from finishing the job.
Taking up another contract, Task force 404 was sent to aid AR squadron from the event of Arctic Warfare.
A later contract would require Task force 404 to dive deep into Ferri controlled territory sector S15 and recover an UAV, but it wasn't as straight forward as it sounds. Deep Dive is an immediate follow up to chapter 8's story, where the UAV containing sensitive Intel was shot down by Dreamer after M16 launched it, the UAV itself crash landed inside Dreamer's control territory.
Deep Dive began with Task force 404 woken up in a basement of a coffee shop. HK416 expressed her frustrations regarding waking up in a messy basement all the time, which immediately backfired, G11 replied with "You always have something to complain about", 45 replied with "You missed the big and clean maintenance room of G&K?". The new contract would require all members of Task force 404 to fit a software for electronic infiltration purposes, 404 was asked to lie down on the maintenance desk again right after their usual maintenance routine to fit the new modules. The newly fitted module would require immediate testing, a combat simulation was set up for them right away to infiltrate a nearby Ferri network, G11 and 416 never took part in electronic attacks before, this would be their very first time entering the Atlas space.
Several tests runs later, the rest of 404 are beginning to notice 45's condition being sub-optimal, she is clearly agitated by something but she does not wish to share with the rest of the team. 416 spoke out for the team, she states that the rest of 404 is worried about 45's condition, with her being the team leader, anything happens to her would drastically effect 404's performance.
Suddenly a signal entered the network uninvited, though it's just a clumsy T-doll of G&K goes by the name SMG KLINKLIN , she logged in from the wrong terminal and trapped her Cloud Atlas in the wrong section of the server. Despite KLIN being unable to discover 404 from that terminal, afraid of the missing T-doll signal being suspicious 45 ordered the team to rescue her in the Atlas space as a training exercise. With KLIN rescue and woke up again at the G&K HQ, 404 disconnected from the network. 45 states that they are use to this module now and the retrieval operation will begin in 12 hours, she informed the team to get some rest.
404's latest contract, at the request of Angelia, they are to assist the newly formed Defiance squadron in their operations against SOCOM units.
- The Art of Girls' Frontline Vol.1, 404 Squad, page 201, HK416